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Organic milk delivers more consistent nutrition across seasons

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organic dairy cowsLike produce, milk quality can vary with the season and year. Dairy cows‘ daily diet, much of which comes from plant forage, determines the nutritional makeup of their milk, so when their food lags in quality, so, too, does their output. And a new study shows that conventionally produced milk is more prone to these unfavorable seasonal shifts than organic milk.

Earlier research had shown slight benefits in organic milk’s nutritional profile when it was tested on the farm. "Whereas on the farms the benefits of organic milk were proven in the summer but not in the winter, in the supermarkets it is significantly better quality year round," Gillian Butler, of the Nafferton Ecological Farming Group at Newcastle University and study co-author, said in a prepared statement.

Butler and her team sampled 22 brands of U.K. milk four times between 2006 and 2008 and found that the organic milk brands had far less seasonal and annual variability. Some of the conventional milk brands, for instance, tended to have higher concentrations of saturated fats and lower levels of beneficial ones, such as omega-3 and polyunsaturated fats after poor growing seasons.

"We didn’t expect to find differences between the sampling periods," Butler said. "But this is likely to be down to the impact of the weather on availability of quality forage."

The researchers suggested that the nutritional profiles reflect a higher quality and more consistent diet for cows in organic milk production. In the U.K., organic production disallows use of nitrogen-based fertilizers, which in turn often leads to more red and white clover in the grass that the cows eat. These plants help cows produce milk that can make for a healthier fatty acid profile. Conventional management, however, might include giving the cows more fat-based supplements that could in turn raise the levels of saturated fats in the milk, according to the researchers.

Butler and her colleagues noted that the new findings have implications for nourishment in a changing climate as well. After the summers that were especially cool and damp in the U.K., such as 2007, the fat profile of conventionally produced milk took an especially noticeable hit. "If these weather patterns continue, both forage and dairy management will have to adapt to maintain current milk quality," Butler said. But, she noted, "The higher levels of beneficial fats in organic milk would more than compensate for the depression brought about by relatively poor weather conditions in the wet year."

The findings were published in the January issue of Journal of Dairy Science.

Image of Gillian Butler and Nafferton Farm cows courtesy of Newcastle University

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  1. 1. lamorpa 8:32 am 01/17/2011

    Brought to you by the Organic Milk Producers Association.

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  2. 2. Notmilkman 9:38 am 01/17/2011

    "Studies have suggested that bovine serum albumin is the milk protein responsible for the onset of diabetes… Patients with insulin-dependent diabetes mellitus produce antibodies to cow milk proteins that
    participate in the development of islet dysfunction… Taken as a whole, our findings suggest that an active response in patients with IDDM (to the bovine protein) is a feature of the autoimmune response."
    – New England Journal of Medicine, July 30, 1992
    "The National Dairy Board’s Slogan, ‘Milk. It does a body good,’ sounds a little hollow these days."
    – Scientific American, October, 1992
    Robert Cohen

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  3. 3. lamorpa 10:59 am 01/17/2011

    And since 1992 (19 years ago) ?

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  4. 4. nhfoley 3:19 pm 01/17/2011

    Well, since 1992, this study was published:

    And a quote from the article about it seems particularly relevant, directly contradicting NotMilkMan’s study:

    "There has been no clear biologic explanation for the lower risk of diabetes seen with higher dairy consumption in prior studies. This is the first time that the relationship of trans-palmitoleic acid with diabetes risk has been evaluated…"

    Not that I am pro-milk, I am somewhat anti-milk… and simply curious.

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  5. 5. Carlyle 3:20 am 01/18/2011

    Areas adjacent to woodland or barns & having a higher incidence of cats preying on field mice, have more clover because the field mice destroy bumble bee nests & bumble bees polinate clover. Did they think of that? How scientific was this study? Were the samples taken from similar geographic & climatic areas for example? Looks like blather science to me.
    Organic milk, if it is produced by hand milking, definitely has more nutrients. Flies, ticks, cow faeces. I used to have an old fashioned dairy. I know what went into the milk.

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  6. 6. bucketofsquid 5:42 pm 01/18/2011

    Has this study been replicated in other countries on a reliable scale?

    Questions for Notmilkman: Which type of diabetes? Is this only in those sensitive to the Albumin since the vast majority of milk drinkers are not diabetic? What about carry over into cheese? Since I’m not diabetic and don’t drink milk, why should I care?

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  7. 7. DairyAdviser 12:45 pm 01/19/2011

    The results of milk sold in the US do not match those of the UK study. While small differences in fatty acid profile were observed between milk sold as organic, rbST-free or with no distinguishing label, the scientists found that "…there were no meaningful differences that would affect public health and that all milks were similar in nutritional quality." These results were also in the May 2010 issue of the J Dairy Science ( In the January 2011 issue of the J Dairy Science, the principal author also had an article which found no seasonal differences in milk fat, which is in contrast to the UK scientists (

    Analysis of these studies suggest that the changes observed by the UK scientists may be limited to the unique conditions for dairying in that part of the world.

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  8. 8. Wayne Williamson 6:06 pm 01/19/2011

    question…does anyone remember the taste/texture of milk changing for them(not counting those that switched to lowfat/alternatives)…over the last 40 years…I don’t….
    Nothing like real milk and cereal/pancakes/cake..etc….

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  9. 9. JDahiya 2:37 am 02/16/2011

    Change in taste over 40 years is more likely linked to getting older than changes in the composition of the food.

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  10. 10. mitra.sripada 9:06 am 05/11/2011

    The taste of milk is same whether it is organic or regular milk and it differs from bottle to bottle and season apart from other factors such as location of the farm, breed of the dairy cow, type of feed fed to dairy cows etc. A slight difference in taste is observed in milk that is subjected to higher heat treatment (ultra high temperature heat treatment).Certain misconceptions are known about freshness of organic milk. The freshness depends upon the speed with which the milk produced in a farm reaches the consumer. In this regard both conventionally produced milk and organic milk score equal because they travel the same distance to reach the consumer’s dining table. Modern day advancement in transport and effective distribution pattern of milk will no doubt help the milk to reach the customer sooner in a fresh state. By consuming organic milk, every individual is supporting the organic dairy farmers indirectly in his efforts to produce a product that is more stringent in its quality and at the same time containing minimum residual limits of harmful contaminants.
    More about organic milk at

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